Selenium
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This often overlooked mineral can greatly reduce joint pain and depression.
It can also prevent hypothyroidism.
Findings reported at the 83rd annual meeting of the Endocrine Society
have pushed selenium into a much greater role in human health. German
physician Barbara Gasnuer of Munich presented evidence that selenium
may help slow the progression of autoimmue thyroiditis, a common inflammatory
condition of the thyroid that often leads to permanent hypothyroidism.
Gasnuer's study looked at 72 women at an average age of 42, all of
whom had autoimmune thyroiditis. Half the patients received selenium
supplementation for three months; the other half received a placebo.
Antibody levels returned completely to normal in nine members of the
selenium group, as compared to just two in the control group. TPO (thyroid
peroxidase) antibody levels decreased significantly in the selenium
group. The patients having the greatest TPO level at the outset of the
study experiencing the most improvement.
Alan Smith, DO conducted a separate study on selenium supplementation
and found significant improvements in muscle and joint problems, thyroid
function, depression, and anxiety. Hair selenium (a common test for
selenium levels) increased 20%, even though levels were acceptable to
begin with.
Our understanding of how beneficial selenium is has grown significantly
in recent years. Gross deficiency (as in areas of China) results in
rapid premature aging. We may have a relative deficiency of selenium
here thanks to our poor Western diet. Researchers have found subtle
deficiencies are associated with atherosclerosis, various types of cancer,
immune dysfunction, male infertility, and now with thyroid function
and mental processes (possibly through thyroid, but perhaps directly
on the brain).
I recommend you take 200 mcg per day. My personal favorite source is
brewers yeast, which has highly bioavailable selenium and is more of
a food than a supplement. Selenium as selenomethionine, 200 mcg, is
an excellent supplemental source. If you're taking Healthy Resolve's
Max Plus (call 800-728-2288 to order), you're getting 200 mcg daily,
but feel free to add some brewers yeast to your diet.
Yours for better health and medical freedom,
Robert Jay Rowen, MD
Selenium is present in all the tissues of the body, but is concentrated
most highly in the kidneys, liver, spleen, pancreas, and testes.
People do not consume enough selenium both because of the type of diet
they eat, and because of the low selenium content of the soil in which
their food is grown.
The selenium content of soil varies widely, with many areas showing
serious depletion. In fact, there have been several reports of selenium
deficiencies in livestock raised on selenium-depleted soil.
Function and Uses of Selenium
Cancer
Selenium's best-known and perhaps most important biological function
relates to its role as an antioxidant and anticancer mineral. As we
have seen in other chapters, free radicals damage our cells, possibly
leading to the development of cancer and other degenerative diseases.
Selenium is an activating component of the enzyme glutathione peroxidase,
which protects our cells from this damage.
Many animal studies have proven that selenium deficiency increases
the incidence and rate of growth of cancers in animals that are either
exposed to a variety of potent carcinogens or receive transplanted tumors.
Companion studies have shown that high selenium intake protects against
these cancers.
For example, in one study in which rats were exposed to a potent carcinogen,
only 15 percent of those who were also given selenium developed liver
cancer as compared with 90 percent of the unsupplemented rats.
In another study, the occurrence of cancer was 10 percent in the supplemented
group versus 80 percent in the control group. In yet another animal
study, selenium supplementation reduced colon cancer incidence by more
than 50 percent.
In another study, selenium protected against UV-induced skin damage
and cancer, retarding the onset and number of skin lesions, and reducing
inflammation, bistering, and pigmentation.
In humans, there is ample epidemiological evidence that high selenium
is correlated with a lower incidence of many types of cancer.
For instance researchers have found that cancer risk is significantly
lower in people living in areas with selenium-rich soil, in people with
a high-selenium food supply, and in people with higher blood levels
of selenium, when compared with people with lower intakes and blood
levels.
Selenium intakes in the people studied were close to 750 micrograms
per day, with no toxic side effects noted.
In a survey that spanned twenty-seven countries, including the United
States, it was found that the cancer death rate was lower in those people
whose typical diets were high in selenium. This and other cancer studies
indicate that selenium is especially protective against cancer of the
breast, colon, and lung.
Data also suggests protection against tumors of the ovaries, cervix,
rectum, bladder, esophagus, pancreas, skin, liver, and prostate, as
well as against leukemia.
Since 1969, it has been known that the blood levels of cancer patients
are low in selenium.
In general, cancer patients with lower-than-average selenium levels
have a greater number of primary tumors, more recurrences, more distant
metastases (tumors that have spread to distant parts of the body), and
a shortened survival time.
In a study of 12,000 people conducted in Finland, the risk of fatal
cancer in people with the lwest levels of serum selenium was nearly
six times higher than that in people with the highest selenium concentrations.
Like other nutrients, of course, selenium cannot do its work alone.
In several studies, it has been shown that selenium and vitamin E, and
perhaps vitamin A, too, have a synergistic effect.
For example, in one study, male smokers who died of cancer had lower
levels of serum selenium, vitamin A, and vitamin E, when compared with
healthy control subjects.
It is well known that vitamin E enhances the antioxidant effect of
selenium. In addition, it has been found that supplementation with selenium
alone and with selenium plus vitamin E in excess of the RDAs stimulates
the immune system in experimental animals.
This effect is particularly pronounced when the diet is high in polyunsaturated
fats- a factor that has been linked to a higher incidence of certain
cancers.
These studies show promise for the prevention and possible treatment
of cancer with selenium supplementation. When combined with other supplements,
the anticancer effect may be even greater.
The National Cancer Inistitute is conducting ongoing "chemopreventive"
trials of several individual nutrients, including selenium, vitamin
E, and vitamin A.
However, often these trials are limited to 200 micrograms of selenium
per day, which may be too low a dose to assess the potential protective
effect of this mineral.
Larger doses of selenium have been shown to be protective in animals,
and safe in humans. In addition, we are not sure of the extent to which
selenium supplementation influences the later stages of cancer development.
If its influence is strongest in the early stage, it will be very difficult
for these trials to prove the connection between low selenium and cancer
because of the long latency period for most cancers.
(For example, it may take up to fourteen years for a single breast
cancer cell to multiply and produce a tumor large enough to be detected
by currently available diagnostic methods.)
Finally, evidence of the synergism of nutrients has led many researchers
to emphasize the need to consider several nutrients in any given diet
and cancer study, instead of focusing on just one nutrient per study.
Cardiovascular Disease
In humans, a link has been found between selenium and heart disease.
People found to have overt selenium deficiencies-alcoholics with cirrhosis
of the liver, and people receiving long-term intravenous feeding-have
also been found to suffer from heart problems that respond to selenium
supplementation. In eastern Finland, which has one of the highest mortality
rates from heart disease in the world, it was found that low selenium
in the blood was associated with up to a six- or sevenfold increase
in the risk of death from heart disease.
In addition, children in certain areas of China in which the selenium
content of the soil is low are known to develop a heart disease called
Keshan's disease. Their heart problems, too, respond to selenium supplementation.
Other Functions
There is some evidence that selenium may also prove effective in the
treatment or prevention of several other disorders.
A study using 400 micrograms of selenium and approximately 25 international
units of vitamin E markedly improved skin conditions such as acne and
seborrheic dermatitis in the test subjects. A Danish study examined
patients with rheumatoid arthritis and found that they had lower levels
of selenium.
Those with the lowest levels had the more severe form of this disease.
Moreover, a recent study conducted in Japan suggests that selenium and
vitamin E may enhance the responsiveness of arthritis patients to conventional
treatment. A fascinating study conducted in Scandinavia showed a correlation
between low selenium levels and the incidence and severity of muscular
dystrophy; one patient who was treated with selenium supplements showed
considerable improvement after one year. Finnish researchers have also
conducted a study on elderly patients, who were given large doses of
selenium and vitamin E for one year.
After two months, researchers found an obvious improvement in their
patients' mental well-being, including less fatigue, depression, and
anxiety, and more mental alertness, motivation, and self-care.
Finally, selenium has been shown to protect against the "TOXIC
EFFECTS" of MERCURY, ARSENIC, and COPPER AND DEFICIENCY SYMPTOMS.
Selenium deficiency symptoms may include muscular weakness and discomfort.
Recent studies have shown that people with celiac disease-an inborn
inability to digest glutenare at high risk for low selenium, along with
other nutrients, either because their lowgluten diets are also low in
selenium, or because of their absorption problems.
Down's syndrome patients have also been found to have low levels of
selenium and other antioxidants.
In one study, refinery workers were found to have low selenium levels
in spite of their dietary intake of 217 micrograms per day, which is
more than three times higher than the RDI. This study indicates that
because of the workers' exposure to free radicals on the job, their
bodies were utilizing large amounts of selenium to produce the protective
enzyme glutathione peroxidase.
This suggests that exposure to toxic environmental chemicals increases
the requirement for this mineral.
The RDI for selenium is 70 micrograms for all men and women.
Food Sources:
There are no accurate available measurements of the selenium content
of foods. However, it appears that the richest sources of selenium are
seafoods, meats, and organ meats-if the animals of origin ate a diet
high in selenium. Whole grains can be good sources, but, similarly,
this depends on the selenium content of the soil in which they were
grown. Fruits and vegetables generally contain very low amounts of selenium.
The refining process strips foods of much of their selenium content.
In one study, it was found that a highly refined diet contains 61 percent
less selenium than does a diet rich in unrefined foods. Cooking also
reduces the content significantly, especially if the cooking water is
discarded. Vitamin C seems to enhance the absorption of selenium.
SUPPLEMENTS
Selenium is most often available as an individual supplement, although
some multivitamin-mineral formulas are beginning to include this mineral.
I recommend selenium in the form of selenomethionine, which is extracted
from selenium-rich yeast or ocean plants. This form is the least toxic
and appears to be the most"absorbable".
OPTIMUM DAILY INTAKE-ODI
For optimum general health, the basic Optimum Daily Intake for selenium
is:
100-400 mcg for men and women living in low-selenium areas this includes
coastal areas and glaciated areas)
50-200 mcg for men and women living in high-selenium areas
The above is excerpted from the book The Real Vitamin & Mineral
Book, by Shari Lieberman, Ph.D and Nancy Bruning, Avery Publishing,
1997
http://www.willner.com/article.aspx?artid=182
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